Obstructive sleep apnoea in acromegaly: the role of craniofacial changes

Obstructive sleep apnoea (OSA) is due to craniofacial changes and acromegaly. The question addressed by this study was whether growth hormone (GH) induced craniofacial changes might explain persisting OSA despite endocrine inactivity in acromegaly. Nineteen patients treated for acromegaly were examined cephalometrically for craniofacial changes and polysomnographically for OSA. Twelve patients proved to have OSA with an apnoea/hypopnoea index >15; seven patients showed no evidence of OSA at all. With respect to the endocrinological parameters, there were no differences between the two groups that would explain the presence or absence of OSA. Neither group differed with respect to sex, age, or body mass index. Craniofacial changes were predominantly found in the mandible. The group with OSA proved to have increased vertical, dolichofacial growth compared to those without OSA. Consecutively, in the OSA group the posterior airway space was narrowed, and the hyoid was displaced more caudally. Thus, it seems that craniofacial structures of patients with acromegaly and persisting obstructive sleep apnoea are different from those without obstructive sleep apnoea. Surgical corrections of pertaining acromegaly-induced craniofacial changes should be performed with an awareness of the individual craniofacial condition so as not to enhance obstructive sleep apnoea.